
Kohler GP1078440
Score: 80/100
Hibbent Toilet Flapper
Score: 80/100Rankings

The Kohler GP1078440 is a genuine 2-inch shark-fin style toilet flapper designed as a replacement part for select Kohler one-piece toilets. It features a corrosion-resistant rubber construction with a red finish and includes an adjustable chain for secure sealing and efficient flushing. This part is specifically engineered for bottom outlet flush valves to ensure a reliable fit.

The Hibbent 2 Pack Toilet Flapper Replacement is a blue rubber flapper designed as a direct replacement for the Gerber 99-788 model, featuring durable material and no-tool installation. It is limited to specific Gerber models, which restricts its universal applicability. It is ideal for DIY repairs in homes with city, hard, or well water, offering a quick, tool-free fix that meets US/Canada plumbing standards.
| Attribute | ![]() | ![]() |
|---|---|---|
2 inches | 3 inchesbest | |
1 count | 2 countbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Material & Durability(2) | ||
Hard Water Resistance | null | true |
Water Resistance | null | true |
Design & Features(3) | ||
Chain Material | Not specified | Stainless Steel |
Installation Type | Direct replacement | No-Tool |
Flapper Type | Shark-fin | Flapper |
Packaging & Support(2) | ||
Pack Quantity (count) | 1 count | 2 count |
Certifications | null | US and Canada Plumbing Code Standards |
Compatibility & Fit(3) | ||
Flapper Diameter (inches) | 2 inches | 3.0 inches |
Toilet Type Compatibility | One-piece | Gerber 99-788 |
Flush Valve Size | 2 | 3 inches |

Products in the top-left offer the best value (high score, low price).

Installation tutorials and video demonstrations highlight the straightforward nature of the replacement, praising the quick setup and the reliability achieved through proper seal cleaning.
Product pages imply positive sentiment regarding leak prevention and water savings, with video demos suggesting that users find the chain adjustments user-friendly and the overall installation process positive.

